The present invention relates to lancing aids for the diagnostic determination of blood parameters. Body fluids are collected and analyzed in many fields of medical diagnostics, and it is therefore desirable to enable routine tests to be carried out outside the laboratory in a rapid and reproducible manner. The testing can be carried out with various body fluids such as, e.g., blood and/or interstitial fluid. These fluids can be examined for various characteristics. The results of this examination are important in order to be able to make reliable diagnoses, to carry out therapeutic measures and for therapeutic monitoring.
The analysis of body fluids starts with collection of the fluid. One method for obtaining body fluid is to generate a very small wound in the skin of the patient with the aid of a needle, lancet or a knife. The body fluid obtained in this manner can then either be collected in small vessels or it can be directly brought into contact with a test element such as a test strip for analysis. In order to avoid injury to the patient when using lancets, needles or blades, the lancing aid is typically constructed with a protector or cover on the lancing tip. Most of these lancing aids require manual insertion of the lancet into the lancing aid. This is a laborious operation when the lancing aid is used frequently. Storage of lancets in a magazine can obviate this problem, but many safety aspects have to be followed. Thus, for example, the safety of the patient during use of the lancing aid must be ensured. Furthermore, the system should not be too complex because otherwise it could not be easily handled by the patient.
A few solutions for this are disclosed in the prior art. U.S. Publication No. 2003/0199902 ensures a sealing of each individual lancet in a magazine in which a complicated and space-filling gear wheel mechanism is used to transport the lancets out of the magazine.
An analytical device is described in the EP 1 203 563. This device has a test element on a carrier tape and an additional frame element is mounted on this test element which is movable and comprises a lancet. During use, the frame element can be moved from a parallel position relative to the test element into an orthogonal position so that the lancet can be actuated through an opening in the test element. This is a quite complicated implementation of a combination of test element and lancet because many parts have to be moved mechanically and the system requires much space in its functional form.
EP 1 360 935 describes an arrangement of lancets (referred to as “testers”) used to obtain liquid samples. The lancets are arranged serially on a tape which has a cover for the lancets on its upper side. A complicated mechanical system is used to expose the lancet for use because the entire lancet body must first be moved out of the plane of the tape in order to be able to use the lancet.
A lancet tape is described in U.S. Publication No. 2004/0193202 in which a part of the lancet body can be bent relative to the tape. A disadvantage associated with this arrangement of tape relative to the lancet is that during a desired lancing movement it is impossible to only move the lancet. Instead, the lancet and tape always have to be moved together. Consequently, a drive mechanism must be selected which is adapted to the tape that includes the lancet. Furthermore, this limitation makes it difficult to achieve a space-saving or uncomplicated design of a simple and light lancing aid.
The prior art devices present a variety of disadvantages. Many mechanical steps are necessary to move the individual lancing element from the magazine store in which the lancets lie in a serial arrangement, i.e., in the plane of the carrier tape, into an arrangement in which the lancet is arranged perpendicular to the plane of the carrier tape. Due to the complicated mechanics, there is an additional disadvantage in that a large amount of space is required for this mechanism. Another disadvantage of many systems of the prior art is the complicated unsealing of the lancet before the lancing operation.
In view of the disadvantages of the prior art, it would be desirable to have a space saving, storable lancing aid that can be used with little mechanical complexity and that enables simple handling.